Abrasive grit exhaust system in grinding machines

ABSTRACT

An abrasive grit exhaust system in grinding machines operating with rotary grinding material comprises a cover adapted to the configuration of the grinding material and connected with a grit exhaust conduit. The cover is divided into a part rotating together with the grinding material and a stationary part connected with the grit exhaust conduit, and the two parts of the cover are tightly interconnected. The part of the cover rotating together with the grinding material is so adapted to the configuration of the grinding material that there is formed between this cover part and the grinding material a gap which opens into the grinding surface of the grinding material being worn and through which the forming abrasive grit is carried off. The cover part mentioned is arranged to be worn down together with the grinding material.

United States Patent Isaksson 1 Jan. 28, 1975 [75] Inventor: Lars Goran Torsten Isaksson,

Hogbyvagen, Sweden [73] Assignee: Teda-Lab I Eskilstuna AB,

Eskilstuna, Sweden [22] Filed: Apr. 12, 1973 [21] Appl. No.: 350,640

[30] Foreign Application Priority Data Apr. 14, 1972 Sweden 4833/72 [52] U.S. Cl. 51/273, 51/170 PT, 51/170 T [51] Int. Cl B24b 55/06, B24b 23/00 [58] Field of Search.... 51/272, 273, 170 PT, 170 T, 51/174, 177

[56] References Cited UNITED STATES PATENTS 2,895,266 7/1959 Statler 51/273 X 3,594,958 7/1971 Cusuman0. 51/273 Primary Examiner-Othell M. Simpson Attorney, Agent, or FirmBucknam and Archer [57] ABSTRACT An abrasive grit exhaust system in grinding machines operating with rotary grinding material comprises a cover adapted to the configuration of the grinding material and connected with a grit exhaust conduit. The cover is divided into a part rotating together with the grinding material and a stationary part connected with the grit exhaust conduit, and the two parts of the cover are tightly interconnected. The part of the cover rotating together with the grinding material is so adapted to the configuration of the grinding material that there is formed between this cover part and the grinding material a gap which opens into the grinding surface of the grinding material being worn and through which the forming abrasive grit is carried off.

down together with the grinding material.

5 Claims, 5 Drawing Figures SBEET 10F 3 FIG.)

ABRASIVE GRIT EXHAUST SYSTEM IN GRINDING MACHINES This invention relates to an abrasive grit exhaust system in a grinding machine equipped with rotary grinding material, and this system comprises a cover adapted tothe configuration of the grinding material and connected with an exhaust conduit. The exhaust system serves to carry off the harmful and/or troublesome grit that arises in grinding with portable and manual grinding machines as well as in stationary grinding machines. Previously, stationary covers have been mounted on the grinding machines and these usually had to be adjusted to ensure full efficiency as the grinding material was worn off.

The present invention has for its object effectively to eliminate this disadvantage and to this end it provides an abrasive grit exhaust system in which the cover is divided into a part rotating together with the grinding material and a stationary part connected with the exhaust conduit, said two parts being tightly interconnected by a labyrinth-type or like seal, and in which the part of the cover rotating together with the grinding material is so adapted to the configuration of the grinding material that there is formed between said cover part and the grinding material a gap which opens into the grinding surface of the grinding material being worn and through which the forming abrasive grit is carried off, said cover part which rotates together with the grinding material being arranged to be worn off together with the grinding material. The part of the cover rotating together with the grinding material thereby ensures a satisfactory exhaust of abrasive grit during the entire life of the grinding material. The part of the cover rotating together with the grinding material and arranged to be worn down with it should be manufactured from plastics, fabric, fiber, metal or other suitable material.

The invention will be more fully described hereinbelow with reference to the accompanying drawings illustrating three embodiments, chosen by way of example, of the abrasive grit exhaust device.

In the drawings:

FIG. 1 is a longitudinal section of a grinding machine provided with one embodiment of the exhaust system and operating with a cup-shaped grinding material;

FIG. 2 is an end view of the part of the cover rotating together with the cup-shaped grinding material;

FIG. 3 is a longitudinal section taken on line IIIIII in FIG. 4 of a grinding machine having an annular grinding disk and provided with a second embodiment of the exhaust system;

FIG. 4 is an end view of a section of the part of the cover rotating together with the grinding disk;

FIG. 5 is a longitudinal section of a grinding machine having a saucer-shaped grinding disk and provided with a third embodiment of the exhaust system.

I designates the grinding machine which in the embodiment shown in FIGS. 1 and 2 is provided with a cup-shaped rotary grinding material 2. The abrasive grit exhaust system comprises a cover which is divided into a part 3 rotating together with the cup-shaped grinding material 2 and a part 4 fixedly connected with the grinding machine 1. The part 3 of said cover is fastened to the member 5 driving the cup-shaped grinding material 2, while the part 4 of the cover is fastened to the neck 6 of the grinding machine 1. An exhaust conduit 7 extends from the stationary cover part 4 and is connected to a grit separator and a suction unit.

The parts 3 and 4 of the cover are tightly interconnected by a labyrinth-type or like seal 8. One member of the seal 8 is disposed on the part 3 of the cover while the other member of the seal 8 is disposed on the part 4 of the cover. Inside the seal 8 the part 3 of the cover is formed with holes 9 for the air escaping from said cover part 3.

The part 3 of the cover rotating together with the cup-shaped grinding material 2 is so adapted to the configuration thereof that a gap 10 is formed between the cover parts 2 and 3, through which gap the forming abrasive grit is exhausted. As will appear from FIG. I the cover part 3 is meant to be worn down together with the cup-shaped grinding material 2. The gap 10 is conformed accordingly; as a rule it is of substantially constant width.

In the embodiment shown in FIGS. 3 and 4 the annular grinding disk 11 is provided on both sides with cover portions 12 and 13 which are adapted to rotate to-.

gether with the grinding disk 11. For this reason they are retained by means of the driving members 14 and 15 and the nut 16. The cover portions 12 and 13 are connected via labyrinth-type seals with the stationary cover portions 17 and 18, the latter of said stationary cover portions being fastened to the neck 19 of the grinding machine. The cover portions 17 and 18 are connected with the common conduit 20 which leads to a grit separator and a suction unit.

The cover portions 12 and 13 are formed by circular plates or like means which are spaced from the sides of the grinding disk 11 so that gaps 21 and 22 are formed between said sides and the plates 12 and 13. The width of the gaps 21 and 22 is determined by spacers 23 and 24 which could directly engage the two sides of the grinding disk 11. In the embodiment illustrated, however, the spacers engage plates 25 and 26 which bear against the sides of the grinding disk. Preferably, the spacers 23 and 24, respectively, are integral with the plates 12, 25 and I3, 26, respectively.

The grinding disk 11 need not be provided with cover portions on both sides. In certain cases it suffices to have one of said cover portions 12 and 13. In the embodiment shown in FIG. 5, the saucer-shaped grinding disk 31 which might also be an ordinary grinding wheel, is provided on one side only with a substantially circular plate 32 which is kept spaced a predetermined distance from said side by spacers 34 to provide the gap 33 necessary for exhausting the abrasive grit. The stationary cover portion 35 is secured to the neck 37 of the grinding machine 36, and connected through the labyrinth-type seal 38 with the rotary cover portion 32 and through the conduit 39 with the grit separator and the suction unit.

I claim:

I. In a grinding apparatus having a rotary grinding wheel and exhaust means for aspirating dust produced by grinding, the improvement which comprises a housing on the apparatus defining an exhaust passage of said exhaust means, and an abradable cover supported for rotation relative to said housing and in unison with the grinding wheel, said abradable cover and a working surface of the grinding wheel being disposed for concurrent abrasrive contact with a workpiece to be ground, said abradable cover being disposed to define with the grinding wheel a gap in flow communication said abradable cover includes a pair of circular plates each disposed in spaced-apart relation to a corresponding end face of the grinding wheel to define therewith respective gaps in flow communication with said exhaust passage.

5. The improvement according to claim 1 wherein said abradable cover has at least one aperture establishing flow communication between said gap and exhaust passage. 

1. In a grinding apparatus having a rotary grinding wheel and exhaust means for aspirating dust produced by grinding, the improvement which comprises a housing on the apparatus defining an exhaust passage of said exhaust means, and an abradable cover supported for rotation relative to said housing and in unison with the grinding wheel, said abradable cover and a working surface of the grinding wheel being disposed for concurrent abrasrive contact with a workpiece to be ground, said abradable cover being dispOsed to define with the grinding wheel a gap in flow communication with said exhaust passage for aspirating through said gap and passage dust produced from grinding.
 2. The improvement according to claim 1 wherein said abradable cover is in the form of a cup laterally surrounding the grinding wheel and open at an end face thereof.
 3. The improvement according to claim 1 wherein said abradable cover includes at least one circular plate disposed in spaced-apart relation to an end face of the grinding wheel.
 4. The improvement according to claim 1 wherein said abradable cover includes a pair of circular plates each disposed in spaced-apart relation to a corresponding end face of the grinding wheel to define therewith respective gaps in flow communication with said exhaust passage.
 5. The improvement according to claim 1 wherein said abradable cover has at least one aperture establishing flow communication between said gap and exhaust passage. 